Abundance and diversity of bees visiting flowering pennycress, a new oilseed crop in the midwestern USA

Oilseed pennycress (Thlaspi arvense) is a new, autumn-sown, “cash cover crop” for the Midwestern USA and elsewhere. Anthesis occurs in early spring when few other plants bloom, and its flowers attract early-emerging bees. However, the taxonomic composition of these bees was unknown. Consequently, we systematically captured and identified the genera and species of bees visiting pennycress flowers throughout anthesis at five site-years: two in Illinois and three in Minnesota. A cumulative total of 28 bee species were found across site-years. The most common genera were Andrena (10 species), Lasioglossum (12 species), and Halictus (2 species). Rarer genera were Apis, Ceratina, Hylaeus, and Nomada. Bee abundance and diversity were related closely and in a negative exponential manner with percent land area devoted to annual cropping. The inclusion of new early flowering crops, such as pennycress, may enhance bee abundance and diversity, especially if even small areas of uncropped land are nearby

Flies associated with floral canopies of the new oilseed crop, pennycress, in the Midwestern U.S.A.

Flies are frequent visitors to flowers of many species of plants within the mustard family (Brassicaceae). They derive nutrition from these flowers, and some fly species are pollinators. Field pennycress (Thlaspi arvense) is a mustard species that is being developed as a new “cash cover crop,” i.e., an autumn-sown cover crop whose oil-rich seeds can be harvested profitably in spring. Although pennycress is largely wind- and self-pollinated, its flowers also attract insect visitors. However, the extent of visitation to pennycress flowers by flies remains largely unknown, especially the identities of those flies. Thus, we examined flies associated with pennycress flowering canopies at five site-years in Illinois and Minnesota. The number of fly species averaged 16 per site-year. Hover flies (Syrphidae) were common visitors to pennycress flowering canopies, representing 24% of all Diptera collected. Toxomerus marginatus (margined calligrapher), whose larvae are aphid predators, was especially abundant within this family. However, the most common flies detected were Delia spp. (Anthomyiidae, root maggot flies), which averaged 51% of all flies collected. Adults of these flies are known pollinators, but their larvae also are pests that can damage seedlings of common summer crops. Although seedling damage to plants that are double- or relay-cropped (i.e., inter-seeded in spring) with pennycress has not been observed yet, close observation of this insect group and its effects may be needed if pennycress is widely sown in the future as a cash cover crop

Limited Seed and Seed Yield Response of Calendula to Applied Nitrogen Does Not Justify Risk of Environmental Damage from High Urea Application Rates

Calendula (Calendula officinalis L.) seed, due to its high calendic acid content, is recognized as a potential environmentally safe substitute for volatile organic compounds. Agronomic guidelines for nitrogen (N) management to produce calendula seed oil on a commercial scale are limited. Post-harvest soil N has the potential to move off-farm and contribute to water quality degradation (e.g., hypoxia in the Gulf of Mexico). Establishing N management guidelines should consider agronomic response and potential environmental risk. Calendula seed and oil yield, oil content, harvest index, N use, seed N use efficiency, oil N use efficiency, agronomic efficiency, vegetative growth, and the amount of residual soil-N following harvest response to five urea N rates (0, 34, 67, 134, and 202 kg N ha−1) were assessed in a replicated field study repeated for two growing seasons. Seed yield increased with N rate, but because of the low N conversion efficiency, there appeared to be minimal yield gains in applying N beyond 34 kg ha−1. The lowest amount of soil-N left underutilized in the soil was predicted to occur at 39 kg N ha−1 and was adequate for seed and seed oil commercial calendula production on a Mollisol in the Northern Midwest United States

Nitrogen Uptake and Use Efficiency in Winter Camelina with Applied N

Maize (Zea mays L.) and soybean [Glycine max (L.) Merr.] rotations in the upper Midwest are highly productive. However, these narrow rotations are followed by a long winter fallow period. Over time, this has contributed to the loss of agroecological functioning, including increased ground water pollution from nitrate-nitrogen (NO3–N). Winter camelina [Camelina sativa (L.) Crantz] is a third crop that could grow during this fallow period, but its nitrogen (N) use and efficiency are not well known. A study was conducted at three locations in the U.S. upper Midwest to determine the N uptake and use efficiency of winter camelina in response to applied N and N application timing. Agronomic efficiency (AE), internal efficiency (IE), and nitrogen recovery efficiency (NRE) tended to decrease with increasing N rates, especially beyond 67 kg N ha−1 in most instances. Total N uptake ranged from 34 to 176 kg ha−1 across N rates, and was on average 1.5 fold the applied rate. Based on the observed decline in N use efficiency with increasing N rates, an application rate of 67 kg N ha−1 appears to balance efficient N use, high yield, and lower environmental risk compared to higher N rates

Pennycress (Thlaspi arvense) a new non-food crop for oil-based biofuel production in Europe and USA

The development of alternative feedstocks for producing oil-based biofuels needs to meet the majority of the following criteria: low cost, high oil content, low agricultural inputs, favorable fatty acid (FA) composition, compatibilitywith existing farm equipment and infrastructure, production in off-season from conventional commodity crops, adaptability to marginal/idle lands, and viable markets for co-products such as seed meal. Recently a “potential weed”, pennycress (Thlaspi arvense L.) has become one of the most attractive new non-food oil crops. Pennycress is highly tolerant to low temperatures, tolerating temperatures below-15°C after reaching a 4-to-6-leaves rosette stage. The seed contains up to 37% oil (DM) with the major fatty acid as erucic (36%). The fatty acid composition in pennycress has been shown to have physical properties suitable for biofuels like biodiesel and hydro-treated renewable jet fuel (HRJ). In the last decade, pennycress has attracted increasing interest as a potential oilseed for biofuel production in the USA, either biodiesel and/or jet fuel, in Europe very few studies have specifically focused on pennycress. In the present study, we compared the productivity of pennycress in response to environment in two European countries, Italy (Bologna) and Greece (Aliartos), and in two USA states, Illinois (Peoria) and Minnesota (Morris). Seed yield, seed oil content and oil compositions were evaluated in response to growing environment. Representative seed samples from each study location was solvent extracted for total oil recovery and compared across locations

Sugars, Hormones, and Environment Affect the Dormancy Status in Underground Adventitious Buds of Leafy Spurge (Euphorbia Esula)

Signals from both leaves and apical or axillary meristems of leafy spurge are known to inhibit root bud growth. To test the hypothesis that carbohydrates and growth regulators affect root bud growth, decapitated leafy spurge plants were hydroponically treated with glucose, sucrose, gibberellic acid (GA), abscisic acid (ABA), 1-naphthaleneacetic acid (NAA), 6-benzylaminopurine (BA), and a GA biosynthesis inhibitor, paclobutrazol. Both glucose and sucrose caused suppression of root bud growth at concentrations of 30 mM. The inhibitory effect of sucrose was counteracted by GA at 15 μM. In contrast, BA, ABA, NAA, and paclobutrazol inhibited root bud growth at concentrations as low as 1, 2, 1, and 16 μM, respectively. Sugar and starch levels were also determined in root buds at various times after decapitation. Buds of intact plants contained the highest level of sucrose compared with buds harvested 1, 3, and 5 d after decapitation. To determine how seasonal changes affect root bud dormancy, growth from root buds of field-grown plants was monitored for several years. Root buds of field-grown leafy spurge had the highest level of innate dormancy from October to November, which persisted until a prolonged period of freezing occurred in November or early December. Our data support the hypothesis that carbohydrates may be involved in regulating dormancy status in root buds of leafy spurge

Winter oilseed pollinators in IA and MN in 2017 and 2018

Data include observations of insect pollinators visiting flowers of two winter oilseed crops (field pennycress and winter camelina) at three sites during the flowering seasons of 2017 and 2018. Two sites were in Minnesota and one site in Iowa each year.Data include observations of insect pollinators visiting flowers of two winter oilseed crops (field pennycress and winter camelina) at three sites during the flowering seasons of 2017 and 2018. Two sites were in Minnesota and one site in Iowa each year. The value of these data are that they document an important agroecosystem service provided by the two novel winter oilseed crops. The purpose of saving the data files in the Digital Conservancy is to abide by new journal requirements that call for universal access to data used in professional qualifications.USDA-National Institute of Food and Agriculture-Coordinated Agricultural Progra

The Environmental Impact of Ecological Intensification in Soybean Cropping Systems in the U.S. Upper Midwest

Introducing cover crops is a form of ecological intensification that can potentially reduce local, regional and global environmental impacts of soybean cropping systems. An assessment of multiple environmental impacts (global warming potential, eutrophication, soil erosion and soil organic carbon variation) was performed on a continuous soybean system in the U.S. upper Midwest. Four sequences were assessed and compared: a soybean cropping system with winter camelina, field pennycress, or winter rye as cover crop, plus a control (sole soybean). Cover crops were interseeded into standing soybean in Year 1, while in Year 2 soybean was relay-cropped into standing camelina or pennycress. Rye was terminated before sowing soybean. When compared with the control, sequences with cover crops showed lower eutrophication potential (4–9% reduction) and soil erosion (5–32% reduction) per ha year−1, in addition to a lower global warming potential (3–8% reduction) when the cover crop was not fertilized. However, when the economic component was included in the assessment, and the results expressed per USD net margin, the sequences with cover crops significantly reduced their performance in all categories of impact considered. A further optimization of field management for camelina and pennycress is recommended to make the cropping system more sustainable